<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0484-7903</journal-id>
<journal-title><![CDATA[Revista mexicana de anestesiología]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. mex. anestesiol.]]></abbrev-journal-title>
<issn>0484-7903</issn>
<publisher>
<publisher-name><![CDATA[Colegio Mexicano de Anestesiología A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0484-79032024000400236</article-id>
<article-id pub-id-type="doi">10.35366/116229</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Optimización de la analgesia epidural: protocolo de evaluación con Ultrasonido Doppler y Modo M para la localización precisa del catéter]]></article-title>
<article-title xml:lang="en"><![CDATA[Optimization of epidural analgesia: proposed protocol for evaluation with Doppler Ultrasound and M Mode for precise catheter localization]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Garduño-López]]></surname>
<given-names><![CDATA[Ana Lilia]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Cruz-Yedra]]></surname>
<given-names><![CDATA[Nabila]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Díaz-Arizmendi]]></surname>
<given-names><![CDATA[Diana Elizabeth]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Verdugo-Velázquez]]></surname>
<given-names><![CDATA[Frida Fernanda]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Acosta-Nava]]></surname>
<given-names><![CDATA[Victor Manuel]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Dominguez-Cherit]]></surname>
<given-names><![CDATA[Guillermo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Lugo-Goytia]]></surname>
<given-names><![CDATA[Gustavo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Macías-Rodriguez]]></surname>
<given-names><![CDATA[Ricardo Ulises]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2024</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2024</year>
</pub-date>
<volume>47</volume>
<numero>4</numero>
<fpage>236</fpage>
<lpage>242</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0484-79032024000400236&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0484-79032024000400236&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0484-79032024000400236&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen:  Introducción:  en la práctica quirúrgica, la analgesia epidural postoperatoria se mantiene como el estándar de oro debido a sus ventajas sobre la analgesia intravenosa con opioides. Sin embargo, el éxito de esta técnica depende en gran medida de la correcta ubicación del catéter en el espacio epidural. Al ser un procedimiento anestésico a ciegas, operador dependiente y en pacientes con diversas características anatómicas, tiene una alta incidencia de falla en la colocación de 12 a 30%. En el postoperatorio inmediato con efectos residuales anestésicos, puede ser difícil detectar de forma temprana la ineficacia del catéter epidural por encontrarse fuera del espacio epidural, lo cual puede favorecer el descontrol del dolor postoperatorio horas más tarde. Múltiples métodos diagnósticos han sido propuestos para la localización de este catéter; sin embargo, muchos de ellos implican dispositivos especiales, que son costosos, invasivos o son métodos poco prácticos en el contexto quirúrgico como la epidurografía.  Objetivo:  obtener una secuencia de pasos para la evaluación adecuada con ultrasonido modo Doppler color y modo M del catéter en el espacio epidural.  Material y métodos:  para la derivación de este protocolo se incluyeron pacientes mayores de 18 años programados para cirugía abdominal o torácica abierta, candidatos a analgesia por catéter epidural torácico, los cuales dieron su consentimiento.  Resultados:  se incluyeron un total de 113 pacientes en el estudio. La media de edad de los pacientes fue de 55.8 ± 15.2 años, de los cuáles 63 (55.8%) fueron mujeres. A través de mediciones con diferentes pacientes se fue optimizando el protocolo de abordaje y se obtuvieron los pasos secuenciales con el ultrasonido.  Conclusiones:  el ultrasonido emerge como una herramienta diagnóstica reciente y prometedora para la localización del catéter epidural, utilizando tanto el Modo M como el modo Doppler color. La derivación de este protocolo proporciona una base sólida para investigaciones futuras, las cuales podrán analizar el rendimiento diagnóstico del ultrasonido en comparación con la epidurografía, así como evaluar su validez interna y externa.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract:  Introduction:  postoperative epidural analgesia in open abdominal or thoracic surgery remains the gold standard due to its advantages over intravenous opioid analgesia. However, the success of this technique relies heavily on the correct placement of the catheter in the epidural space. Being a blind, operator-dependent procedure, and in patients with diverse anatomical characteristics, there is a high incidence of placement failure ranging from 12% to 30%. In the immediate postoperative period with residual anesthetic effects, early detection of epidural catheter inefficacy due to misplacement outside the epidural space can be challenging, potentially leading to postoperative pain uncontrolled hours later. Multiple diagnostic methods have been proposed for catheter localization; however, many involve special devices that are costly, invasive, or impractical in the surgical setting like epidurography.  Objective:  to establish a sequence of steps for the adequate evaluation of the catheter in the epidural space using ultrasound.  Material and methods:  patients over 18 years of age scheduled for open abdominal or thoracic surgery candidates for thoracic epidural analgesia, who provided consent.  Results:  a total of 113 patients were included in the study. The mean age of the patients was 55.8 ± 15.2 years, with 50 (44.2%) being 63 (55.8%) female. The ultrasound-guided approach protocol was optimized through measurements with different patients.  Conclusions:  ultrasound emerges as a recent and promising diagnostic tool for locating the epidural catheter, utilizing both the M-mode and color Doppler mode. This protocol provides a solid foundation for future research, which will be able to analyze the diagnostic accuracy of ultrasound compared to epidurography, as well as evaluate its internal and external validity.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[analgesia epidural]]></kwd>
<kwd lng="es"><![CDATA[catéter epidural]]></kwd>
<kwd lng="es"><![CDATA[ultrasonido doppler color]]></kwd>
<kwd lng="es"><![CDATA[modo m]]></kwd>
<kwd lng="es"><![CDATA[localización del catéter epidural]]></kwd>
<kwd lng="es"><![CDATA[falla de colocación de cateter epidural]]></kwd>
<kwd lng="en"><![CDATA[epidural analgesia]]></kwd>
<kwd lng="en"><![CDATA[epidural catheter]]></kwd>
<kwd lng="en"><![CDATA[color doppler ultrasound]]></kwd>
<kwd lng="en"><![CDATA[mode m]]></kwd>
<kwd lng="en"><![CDATA[epidural catheter localization]]></kwd>
<kwd lng="en"><![CDATA[epidural catheter misplacement]]></kwd>
</kwd-group>
</article-meta>
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